Test Your Knowledge

Tonsillitis is inflammation or swelling of the tonsils. Viruses or bacteria transmitted to the tonsils cause the infection.

The tonsils are oval-shaped masses of tissue located inside the mouth, on either side of the throat. They are located toward the back of the throat – just behind and above the tongue. The tonsils should not be confused with the fleshy lobe (uvula) that hangs down the back of the throat.

Different children may have different-sized tonsils – there is no one size typical for all children. The tonsils are generally small at birth and gradually get larger until a child is about 6 or 7 years old. At that point, the tonsils begin to decrease in size, although they never completely disappear.  

The tonsils perform an important immune system function. They are made up of infection-fighting lymphoid tissue. This tissue stores lymphocytes (white blood cells) that destroy viruses and bacteria entering the body through the mouth or nose. The tonsils typically collect and destroy these invading organisms. Tonsillitis occurs when the tonsils are overwhelmed during this process, becoming red and swollen.

Like the tonsils, the adenoids (a mass of tissue located above the throat and behind the nose) also works to fight infectious viruses and bacteria that may enter the body. However, it is difficult to see the adenoids during a visual inspection of a child’s mouth.

Tonsillitis is a contagious infection that is rare in infants. Most cases of tonsillitis occur during childhood, although the infection may occur at any time in a person’s life. Almost all children in the United States develop tonsillitis at least once, according to the American Academy of Otolaryngology – Head and Neck Surgery. It is not unusual for tonsillitis to recur. Tonsillitis is especially common in environments where people are in close contact for hours every day (e.g., school, playground, daycare).

Tonsillitis is different from other conditions that may also cause a sore throat, but do not necessarily involve the tonsils. These conditions include:

• Pharyngitis. Inflammation of the pharynx (back of the throat). Pharyngitis may be caused by viruses or bacteria. It often accompanies tonsillitis.
  
  
• Coxsackie infection. Viral infection that usually begins in the throat. Symptoms include difficulty swallowing, fever and blisters in the throat, including on the tonsils. Also called hand, foot & mouth disease.
  
  
• Chickenpox. Common viral infection that may cause a sore throat.
  
  
• Croup. Common childhood condition that involves breathing difficulty due to swelling of the voice box (larynx) and windpipe (trachea). Croup may be caused by viruses or bacteria and involves a distinctive barking cough.
  
  
• Measles.  Viral infection that affects the respiratory system and can cause a spreading rash. Immunization prevents measles.
  
  
• Mumps. A viral infection that affects the salivary glands and causes painful swallowing and swollen cheeks. Mumps was formerly a common childhood disease, but the measles, mumps, rubella (MMR) vaccine has made all three illnesses rare in the western industrialized world.
  
  
• Diphtheria. Bacterial infection that can cause breathing difficulties and painful swallowing. Diphtheria is rare since most children are vaccinated against it.